1. Field of the Invention
The present invention relates to a starter used in starting an engine of, for example, an automobile or the like.
2. Description of the Related Art
A starter of a background art is constructed by a constitution including a fuse in series with a suction coil constituting a starter. (Refer to, for example, JP-A-2005-54706, page 10, FIG. 2)
Further, also in a starter of a background art having an auxiliary switching function is constructed by a constitution including a fuse in series with a suction coil constituting the starter. (Refer to, for example, JP-A-2004-52572, page 8, FIG. 1)
A general starter is constructed by a constitution in which by closing a start switch provided for starting the starter, a pinion gear provided to the starter and a ring gear provided to an engine are brought in mesh with each other, and a rotating operation of the starter is transmitted to the engine and therefore, in a case in which teeth of both of the pinion gear and the ring gear collide with each other and are not brought in mesh with each other normally, and in a case in which the start switch for starting the engine is continuously closed and the suction coil is conducted with electricity for a long period of time or a case in which an operation of opening the start switch once and thereafter immediately closing the start switch is continuously carried out repeatedly and the suction coil is intermittently conducted with electricity for a long period of time, there is a concern that a temperature of the suction coil rises, an insulating coating of the suction coil is melted to bring about layer short circuit, and a short circuit current flows.
Therefore, according to the starter of the background art, there is used a fuse a melting temperature of which is set to be low to be connected in series with the suction coil such that electricity conduction to the suction coil is cut before bringing the suction coil into layer short circuit, however, the fuse is comparatively easily melted to cut by conducting normal current and therefore, by cutting the fuse, the starter is not operated, and the state in which the engine cannot be started is brought about frequently.
Further, according to the starter of the background art, a resistance value of the fuse varies widely from high and low owing to production tolerance or the like, as a result, a current having a value different from a normal value flows in the fuse, a temperature rise of the fuse is changed and also a time period of cutting the fuse becomes a different value. Hence, when the fuse is melted to cut by a time period shorter than normal, that is, there is further frequently brought about the state in which the engine cannot be started, and it is difficult to design a fuse melted to cut by a predetermined time period for avoiding the state.